1. Field of the Invention
The present invention relates to a method of fabricating a semiconductor package. More particularly, the present invention relates to a die attaching method for attaching a semiconductor chip onto a die pad of a base frame.
2. Description of the Related Art
Recently, electronic appliances have become smaller and thinner. Accordingly, semiconductor packages employed by today's electronic appliances must be suitably small and thin. Thus, new methods of manufacturing small and thin semiconductor packages are continuously being developed. For example, a technique of grinding the back side of a semiconductor chip has been developed for producing a thin semiconductor package. In this case, the semiconductor chip can have a thickness of 100 μm or less.
A semiconductor package is manufactured by attaching a semiconductor chip to a base frame such as a lead frame or a printed circuit board, electrically connecting the semiconductor chip and the base frame with bonding wires or (solder) bumps, and encapsulating the semiconductor chip in a sealing resin. However, in the case in which the back side of the semiconductor chip is ground, because of its thinness, the semiconductor chip may warp or crack during its handling.
In order to prevent such a problem, the semiconductor chips are fabricated from a wafer, a protective tape is attached to a front surface of the wafer, and the wafer is then sliced to separate the wafer into individual semiconductor chips. The protective tape also prevents the front surface of the wafer from being contaminated by silicon particles that are inevitably generated during the slicing process.
FIG. 1 is a flow chart of that portion of a method of assembling a semiconductor package wherein the semiconductor chip is attached to a base frame (hereinafter referred to as a “die-attaching method”).
Referring to FIG. 1, first, protective tape is attached to the front surface of a wafer and the bottom surface of the wafer is ground (S10). Subsequently, the wafer is attached to a film type of die attaching tape (S20). The wafer is then cut by a blade to separate the semiconductor chips from one another (S30). The individual (unit) chips are then separated from the film type of die attaching tape, and are each attached on a die pad of the base frame; that is, the die attaching process is performed (S40). After the die attaching process is performed, the protective tape is irradiated with ultraviolet rays to weaken the adhesive force, and an adhesive strip is attached to the protective tape and then pulled to remove the protective tape (S50).
However, according to the conventional art described above, the protective tape must be removed (representing an additional process in the manufacturing of the package), and equipment for removing the protective tape is thus required. Accordingly, this additional process impacts the productivity of the prior art processes for fabricating semiconductor packages.